Yu Jianxun, Tan Fengze, Yu Changyuan
Photonics Research Centre, Department of Electronic and Information Engineering, The Hong Kong Polytechnic University, Hong Kong, China.
The Hong Kong Polytechnic University Shenzhen Research Institute, Shenzhen 518057, China.
Sensors (Basel). 2022 Feb 25;22(5):1809. doi: 10.3390/s22051809.
With the widespread use of few-mode fibers, mode characteristics testing becomes essential. In this paper, current few-mode fiber testing techniques are discussed, and the S imaging technique is chosen and demonstrated to be capable of few-mode fiber characterization in principle. As a result, the few-mode fiber characterization system with the S imaging technique is built and used to obtain accurate mode dispersion of two-mode fibers (a commonly used few-mode fiber) of different lengths. Then, various filters are applied to extract the fundamental and high-order modes to acquire mode coupling components (discrete and distributed mode coupling). The proposed system spectrally characterizes the few-mode fiber by resolving the interference information from the superimposed optical field spatially and has a simple structure and easy operation, which will provide parameter guidance for FMF designing and the FMF sensing experiment optimizing.
随着少模光纤的广泛应用，模式特性测试变得至关重要。本文讨论了当前的少模光纤测试技术，并选择了S成像技术，证明其原则上能够对少模光纤进行表征。因此，构建了具有S成像技术的少模光纤表征系统，并用于获取不同长度的双模光纤（一种常用的少模光纤）的精确模式色散。然后，应用各种滤波器提取基模和高阶模，以获取模式耦合分量（离散和分布模式耦合）。所提出的系统通过在空间上解析叠加光场的干涉信息来对少模光纤进行光谱表征，具有结构简单、操作简便的特点，将为少模光纤设计和少模光纤传感实验优化提供参数指导。
